Copy the code below to embed the WBUR audio player on your site

A man exhales vapor produced by an e-cigarette in Bristol, England. (Matt Cardy/Getty Images)

One-in-seven adults in the U.S. have tried e-cigarettes, or vapes, according to new research published Tuesday in the Journal of The American Medical Association. The study also showed a slight decline in continued use.

Despite opposition from researchers and other critics, the vaping industry is now worth billions of dollars, and some worry that the trend has taken hold in high schools around the country.

Here & Now's Jeremy Hobson speaks with Stanton Glantz (@ProfGlantz), director of the Center for Tobacco Control Research and Education at the University of California San Francisco, who says research shows e-cigarettes are linked with significant health problems.

"We've made huge progress in denormalizing tobacco use and making the cool thing to do to be a nonsmoker," Glantz says. "Until e-cigarettes came along, total tobacco and nicotine consumption was dropping, and at least with youth it's now increasing."

Interview Highlights

On how e-cigarettes work compared to conventional cigarettes

"Well the way a cigarette works is you burn the tobacco to generate an aerosol of ultra-fine particles and nicotine, which is the addictive drug, and tobacco products down deep into your lungs where it gets absorbed, and then quickly goes to your brain. E-cigarettes generate an aerosol of ultra-fine particles by taking a solution of nicotine, propylene glycol, glycerol flavors and other things, and it absorbs it into a wick, and then there's a heater coil — kind of like the heaters you see in toasters — wrapped around the wick that generates the aerosol that people inhale to take the nicotine deep into their lungs."

On if e-cigarettes are safer than conventional cigarettes

"E-cigarettes produce lower levels of cancer-causing chemicals than conventional cigarettes do. But just like conventional cigarettes, they help to cause heart disease and heart attacks, lung disease, and in fact, there's growing evidence that in terms of adverse effects on the lung, e-cigarettes are actually worse than conventional cigarettes."

On the amount of nicotine inhaled from an e-cigarette versus a regular cigarette

"It's very variable. It depends on the level of concentration in the nicotine liquid, which you put in the e-cigarettes and also things like the voltage that the e-cigarette is running at. There's also a new form of e-cigarette called JUUL, which instead of dissolving the nicotine and propylene glycol, uses a salt of nicotine and that gives much higher levels of nicotine."

"There's growing evidence that in terms of adverse effects on the lung, e-cigarettes are actually worse than conventional cigarettes."

Stanton Glantz

On the myths that e-cigarettes are healthier

"One of the incorrect things that a lot of people think about e-cigarettes is they're just harmless water vapor. Well, water vapor is clear, and you're breathing out a huge plume of propylene glycol. Nicotine, and also because of the coils in the cigarettes, the fact that they're soldered, people get a lot of lead, cadmium and other heavy metals."

On the use of e-cigarettes to quit smoking regular cigarettes

"One of the major reasons people use e-cigarettes, especially adults, is because they think they'll help them try to quit. For most people they actually make it harder to quit.

"Well nobody knows for sure, but a couple of reasons people talk about are that a lot of people will use e-cigarettes in places they're not allowed to smoke. People think they're safer, and they think that if they use e-cigarettes that they're reducing their risks. And we found that the use of the e-cigarettes and the cigarettes compound. So if you're using cigarettes and e-cigarettes at the same time, which is what most people do, you actually are at higher risk of a heart attack."

On why e-cigarettes are popular among kids

"Products like JUUL, which produce a lower volume of aerosol because the nicotine concentration is so much higher or even easier for people to hide. And it's part of the game and part of the rebellion of using e-cigarettes for kids is that you use them right in class, and the teacher doesn't even know it.

"JUUL is wildly popular with kids, and unlike conventional cigarettes where youth use them as a way to emulate adults, the e-cigarette epidemic has really grown from the young kids up into the adults. So e-cigarette market penetration in the youth market is way higher, and the JUUL is, it's cool. It looks like a flash drive; it's very high-tech. You get a huge nicotine hit from it, and it comes in fun flavors.

"The tobacco companies have said for decades that they don't want kids to smoke when in fact, if they don't get kids to smoke, then their market dies out. And you know, JUUL says — and other e-cigarette companies which include the major cigarette companies — all say they don't want kids to use the product. But there's lots of things they could do if they really didn't want kids to use the product. For example, they would stop making them in these kid friendly flavors."

"The tobacco companies have said for decades that they don't want kids to smoke when in fact, if they don't get kids to smoke, then their market dies out."

Stanton Glantz

On the long-term health effects of e-cigarettes

"Well, we don't know the long-term health effects because we have to wait a long time to know what the long-term health effects are. But we already know that they are very bad for your lungs, that they trigger a lot of inflammatory processes, that they depress your immune processes in your lungs and make it easier to get infected. We know that they turn off normal functioning of arteries the way that conventional cigarettes do. And as I said, we have research we've done that shows that people who use e-cigarettes daily have an almost doubling of the risk of having had a heart attack, and that's on top of that heart attack risks of any cigarette smoking that they are doing. And they're also very, very attractive to kids. About a third of the kids who initiate nicotine use with e-cigarettes have psychological profiles that make you think you it would be very unlikely they would never pick up a cigarette. But once they start with e-cigarettes, a lot of the kids then convert to conventional cigarettes."

On how regulation of e-cigarettes needs to change

"It was very disappointing because when Obama was still president, the [Food and Drug Administration] tried to put in place rules severely restricting the use of flavors, and the Obama White House cut those rules out. The FDA under Trump up until recently had been really moving very, very slowly to address flavors, but I think the explosion of JUUL and flavored tobacco products is really concerning the FDA, and they're at least talking about doing some things. The real action though on these things is happening — as most things in tobacco — at the local and state level. For example here in California and in many other places, you can't use e-cigarettes in places that you can't smoke. Here in San Francisco, the city passed a law prohibiting the sale of any flavored tobacco products including flavored e-cigarettes. R.J. Reynolds Tobacco spent about $12 million so far forcing a referendum on that law, which will be voted on in the June election."

Here & Now received this statement from JUUL Labs, which makes e-cigarette products, in response to Glantz's concerns about the company's marketing practices, and its products' popularity among young people:

"Our company’s mission is to eliminate cigarettes and help the more than one billion smokers worldwide switch to a better alternative. At the same time, we are committed to deterring young people, as well as adults who do not currently smoke, from using our products. We cannot be more emphatic on this point: No young person or non-nicotine user should ever try JUUL.

"We want to work with lawmakers, FDA, parents, educators and community leaders to address underage use. Under the guidance of tobacco control experts and public officials led by Iowa Attorney General Tom Miller, we’ve committed $30 million to independent research, youth and parent education and prevention, and community engagement. We want to be part of the solution in helping to keep JUUL out of the hands of young people."